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Accounting for Derivative Instruments and Hedging Activities - Fair Value Within the Derivative Instrument Valuation (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Derivative assets	$ 1,081	$ 783
Derivative liabilities	977	680
Interest rate contracts current
Derivative [Line Items]
Derivative assets	17	8
Derivative liabilities	0	1
Interest rate contracts long-term
Derivative [Line Items]
Derivative assets	22	31
Derivative liabilities	0	5
Commodity contracts current
Derivative [Line Items]
Derivative assets	747	616
Derivative liabilities	673	536
Commodity contracts long-term
Derivative [Line Items]
Derivative assets	295	128
Derivative liabilities	$ 304	$ 138

X

- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 10
-Section 50
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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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